Umbrella



FIG. 1 is a perspective view of an umbrella showing my new design;

FIG. 2 is a front view thereof;

FIG. 3 is a top view thereof;

FIG. 4 is a bottom view thereof;

FIG. 5 is a right-side view thereof; and,

FIG. 6 is a left-side view thereof.

The support post on the umbrella is shown fragmented on the lower end for ease of illustration. 

I claim the ornamental design for an umbrella, as shown and described. 